The present disclosure relates to digital image modification. A digital image can originate from an input device, such as a digital camera or a digital scanner. A digital image can also be synthesized using mathematical functions or geometric models. Once captured or created, a digital image can be modified electronically to produce a number of variations of the image.
An image can be represented electronically as a grid of information units known as pixels. Each pixel contains color, brightness, and other information about a single point in the image. The greater the number of pixels used to represent an image, the higher the resolution of the image and generally the more realistic the image appears to a human observer. An image can be modified by changing the information contained in a pixel or group of pixels. The number of pixels can also be increased through extrapolation to produce a higher-resolution image or can be decreased through merging to produce a lower-resolution image. The sophistication of the image modification process and the level of detail in the original image can affect the quality of a modified digital image.
Human visual perception is extremely complex and relies on many subtle visual and contextual cues to interpret an image. Digital photography typically captures a scene with sufficient nuance and detail to produce a digital image that appears realistic to a human observer. Digital images that capture or synthesize a scene with sufficient nuance and detail to appear realistic to a human observer are said to be “photorealistic.”